Landing gear and flap control for tethered model airplanes



Feb. 5, 1952 HYATT 2,584,588

I LANDING GEAR AND FLAP CONTROL FOR TETHERED MODEL AIRPLANES Filed March 21, 1947 INVENTOR.

6 6 ATTORN EYS.

Patented Feb. 5, 1952 asstsss I LANDING-GEAR AND FLAP-CONTROL FOR TETHER EDiMODEL AIRPLANES Darwin E. Hyatt, Roscoe, Calif.

. Application March'21, 1947, Serial No."736,341

,The present invention relates: toxmodel Lair- -planes and in particular toimproved control .means therefor.

An object of the present inventiomis to provide in a model airplane control means whiehq are automatically actuated in response-to the speed of the airplane for controlling either-the position of the landing gear of the airplane or the positional. its vflaps.

7 Another object of the present invention is to and of relatively small physical size for: controlling the position .of the. landing gear and/or flapsrof the airplane.

Still another object of the present :invention Z GIaimS. (Chili- 77) .10 provide a centrifugallyyactuated control;means in a model airplane of lre1atively light weight is to provide an improvedcontrol cooperatively v associated withconventional controlsnow pres.-

ent on existing airplanes of the type in which thev elevator of the plane: is controlled vbymovement of attached controlzstrings. ,This new tive relationship to the landing gear "for movingzsame.

t Figure 'Z'ihGWS a portion of the apparatus 'mounted in Figure l inoperative relationshipto one of the flaps for controlling the position; of same 7 Theairplane shown in Figure 1 has an elevator H3 whose position. may be controlledby manual operation of the hand grip .l 1 through the intermediate flexible connecting'cords 1.2 and l3, and

also. has a pair of flaps I5 and [6- together with landinggear H and 18. 'The position of such landing gear and ailerons are controlledautomatically in accordance with the speed of the model airplane which may be powered by an internal combustion engine carried thereon. The

path of movementof the airplane model through the air by a-self-contained powersource, with such'model held captive by the guide cords I2, 13,

connected to-the walking beam member 2!, is in a -circle-about the operator graspin the handle I I,

controlis effective toautomaticallylcontrol the positionof the landing gear and flaps.

Yet another object of the present-invention is to provide an improved: control arrangement forvcontrolling. all ;'of the essential control elements of a modelairplane, characterized byits simplicity, lightness,-=compactness and ease of manufacture. I a

*The features 'of'the present invention'which are believed tobe novel :areset forth-withpar- V ticularity in the appended claims. This invention itself, both as to its'organization and manner of operation, together with further objects and advantages thereof, may be best understood by reference to the following description taken in connection with the accompanying drawings in which: v

Figure 1 is a perspective view of a model airplane with flexible controlling means extending;

therefrom, the airplane incorporating the apparatus embodying the present invention for con trolling not only the elevator-but also the landing gear-and/or flaps. g V

Figure 2 is a top plan view of a portion ofrthe apparatus mounted "in the airplane shown in Figure 1.

Figure 3 is a sectional view taken substan-v tially on the line 33 of Figure 4. r

' Figure 4 is asectional view taken substantially;

on the line 44 of Figure 2.

Figure 5 is a sectional view taken substantially on the line 5--5 of Figure 4. V Figure 6 shows a plan view of a portion of the apparatus of Figure 2 connected in operathe operator being at the center of such circle with the model airplane flying-in a circle-the radius "of which is the length of thecords l2, 13. 'The speed of the model airplane causes centrifugal *forces to act-on the control mechanism comprising the beam member 2| and lever 244- Such centrifugal force varies, of course, as

the-speedof the model so that the termfcentrifugal Iorceactuated means used in the specification andclaims relates to the resulting forces acting on the beam member 2| and lever 24 'Whenthe model airplane flies in the above-mentioned circle. the position of the elevator I0 may be con- The fiight'of the airplane and trolled. by simple Wrist movement of the hand which grips the hand grip ll, motion of the connecting cords l2 and I3 being transferred to the elevator control rod!!! through an inter- 'mediate pivoted walking'beam link member 21 This walking beam member 2| isfastened at a point intermediate its ends by means of the bolt and nut-connection 22, 23 to the lever-member 24 having one of its ends journaled for rotation on the pivot pin 25, which is stationarily mounted on the bracket members 25 and 27. These bracket members 215 and 21 are in turn riveted together and the unit thus formed is riveted to vthe bottom frame member "28, which is conveniently fastened to the fuselage with the-apparatus thereon located symmetrically about the longitudinal center line of the airplane.

The lever member 24 is normally biased to a predetermined position by means of the compression spring 30 having one of its ends recessed in ends connected to retracting gear actuating rods 45, 46 and also to the flap actuating rods 41, 48.

The compression spring normally maintains the lever member 40 in such position that the landing gear [1, l8 and flaps l5, l6 are extended to the positions where they are most effective in landing and takeoff operations. The landing gear I8 and the flaps |5, |6 are automatically moved,

by centrifugal force actuated means comprising the walking beam member 2| and lever 24 when the airplane attains a predetermined speed without the necessity of operating the hand grip Upon the attainment of said predetermined speed the centrifugal forces acting on the assembly comprising the walking beam member 2|, and the lever member 24 serve to pivot such assembly about the pivot pin 25 against the action of the compression spring 3|]. In the resulting movement of such assembly the pin member secured to the lever member 24 engages and causes the lever member to pivot about its pivot pin 4| to thereby produce resulting movement of the control rods 45, 46, 41 and 48.

The landing gear l8 may be connected to the control rods 45 and 46 in many different ways for pivoted movement thereby; for example, the landing gear I8 may have each unit thereof pivotally mounted within the fuselage or in the wing structure on stationary pivot pins 5|) and 5| respectively with the extremities of the rods 46, 45 connected to the pivoted landing gearunit to thereby cause movement of the landing gear unit I! and |8 inwardly and towards one another when and as the levermember 46 is rotated as indicated in Figure 1.

In a similar manner the flaps l5 and 6 are pivotally mounted respectively on bell crank members such as the bell crank member 60 journaled for rotation in the wing structure. The bell crank for flap I5 is not shown but is the same in structure as the bell crank 60 and is mounted opposite the flap l5 in the same manner as is the bell crank '60. The bell cranks for flaps l6 and I5 have arms thereof connecting control rod 48 to flap 16 on the one hand and connecting control rod 41 to flap I5 on the other hand to thereby automatically slide the flaps I5 and 16 out of the confines of adjacent wing structures during landing andtakeoff operations. These flaps, as seen in Figure 1, are curved downwardly to produce air spoiling and braking action. Of course, in normal flight, the flaps |5, US are automatically retracted within the confines of the wing structures and are only effective during landing and takeoff operations.

It is apparent that the airplane may be manufactured to incorporate only the automatic retractable landing gear structure oi, on the other hand, the airplane may be manufactured to incorporate only the automatic retractable flap 4 structure, the movable elevated structure being present in either case.

While the particular embodiments of the pres ent invention have been shown and described, it will be obvious to those skilled in the art that changes and modifications may be made without departing from this invention in its broader aspects and, therefore, the aim in the appended claims is to cover all such changes and modifications as fall within the true spirit and scope of this invention.

I claim:

1. In a self-propelled model airplane, flexible control means extending from said airplane, stationary bracket means mounted on said airplane, a first lever member pivoted on said bracket means, a second lever member pivoted at a point intermediate its ends on said first lever member, said flexible control means being attached to opposite ends of said second lever, an elevator mounted on said airplane, means connected between said elevator and said second lever for opv erating said elevator in accordance with motion of said fiexible control means, resilient means between said first lever and said bracket means, a third lever pivotally mounted on said bracket means, a landing gear mounted on said airplane, means connecting said third lever to said landing gear and means connecting said first lever to said third lever to thereby produce motion of said landing gear in accordance with centrifugal forces acting on the assembly comprising said lever members.

2. In a self-propelled model airplane, flexible control means extending from said airplane, stationary bracket means mounted on said airplane, a first lever member pivoted .on said bracket means, a second lever member pivoted at a point intermediate its ends on said first lever member, said flexible control means being attached to opposite ends of said second lever, an elevator mounted on said airplane, means connected between said elevator and said second lever for operating said elevator in accordance with motion of said flexible control means, resilient means between said first lever and said bracket means, a third lever pivotally mounted on said bracket means, a flap, said flap being mounted on said airplane, means connecting said third lever to said flap, and means connecting said first lever to said third lever to thereby produce motion of said flap in accordance with centrifugal forces acting on the assembly comprising said'lever members.

' DARWIN E. I-IYATT.

REFERENCES CITED The following references are of record in the file of this patent UNITED STATES PATENTS Germany Nov. 17, 1938 

